title: The advantage of circulating tumor cells over serum carcinoembryonic antigen for predicting treatment responses in rectal cancer.
abstract: OBJECTIVE
  The objective of this study was to investigate the clinical significance of circulating tumor cells (CTCs) on the evaluation and prediction of treatment responses in rectal cancer patients compared with serum carcinoembryonic antigen (CEA).
  
  
  METHODS
  Both CTCs and CEA levels of 103 rectal cancer patients (66 with stage II-III and 37 with recurrence or metastasis) were analyzed before and after chemoradiotherapy. CTCs were detected using EpCAM magnetic bead-based enrichment combined with cytometric identification.
  
  
  RESULTS
  CTCs were detected in all patients while no tumor cells were found in healthy controls. CTC levels in metastatic patients were significantly higher than those with recurrence or stage II-III rectal cancer. There is a close relationship between CTC levels and treatment outcomes but serum CEA did not have any correlation.
  
  
  CONCLUSIONS
  CTCs are promising markers for the evaluation and prediction of treatment responses in rectal cancer patients, superior to the conventional tumor marker CEA.
authors.affiliation: Department of Radiation Oncology, Fudan University Shanghai Cancer Center, No. 270, Dong'an Road, Shanghai 200032, China.
authors.forename: Wenjie
authors.initials: W
authors.lastname: Sun
authors.forename: Ting
authors.initials: T
authors.lastname: Huang
authors.forename: Guichao
authors.initials: G
authors.lastname: Li
authors.forename: Weiqi
authors.initials: W
authors.lastname: Shen
authors.forename: Ji
authors.initials: J
authors.lastname: Zhu
authors.forename: Qinghui
authors.initials: Q
authors.lastname: Jin
authors.forename: Jianlong
authors.initials: J
authors.lastname: Zhao
authors.forename: Chunping
authors.initials: C
authors.lastname: Jia
authors.forename: Zhen
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D000328:Adult; D000368:Aged; D002272:Carcinoembryonic Antigen / Q000097:blood*; D045744:Cell Line, Tumor; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D009360:Neoplastic Cells, Circulating / Q000473:pathology*; D012004:Rectal Neoplasms / Q000097:blood* / Q000175:diagnosis / Q000473:pathology* / Q000628:therapy; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome
chemical_list: D002272:Carcinoembryonic Antigen